96 lines · cpp
1//===----------------------------------------------------------------------===//2//3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.4// See https://llvm.org/LICENSE.txt for license information.5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception6//7//===----------------------------------------------------------------------===//8// UNSUPPORTED: c++03, c++11, c++14, c++179 10// <chrono>11// class year_month;12 13// constexpr year_month operator-(const year_month& ym, const years& dy) noexcept;14// Returns: ym + -dy.15//16// constexpr year_month operator-(const year_month& ym, const months& dm) noexcept;17// Returns: ym + -dm.18//19// constexpr months operator-(const year_month& x, const year_month& y) noexcept;20// Returns: x.year() - y.year() + months{static_cast<int>(unsigned{x.month()}) -21// static_cast<int>(unsigned{y.month()})}22 23#include <chrono>24#include <cassert>25#include <type_traits>26#include <utility>27 28#include "test_macros.h"29 30using year = std::chrono::year;31using years = std::chrono::years;32using month = std::chrono::month;33using months = std::chrono::months;34using year_month = std::chrono::year_month;35 36constexpr bool test() {37 { // year_month - years38 39 year_month ym{year{1234}, std::chrono::January};40 for (int i = 0; i <= 10; ++i) {41 year_month ym1 = ym - years{i};42 assert(static_cast<int>(ym1.year()) == 1234 - i);43 assert(ym1.month() == std::chrono::January);44 }45 }46 47 { // year_month - months48 49 year_month ym{year{1234}, std::chrono::November};50 for (int i = 0; i <= 10; ++i) {51 year_month ym1 = ym - months{i};52 assert(static_cast<int>(ym1.year()) == 1234);53 assert(ym1.month() == month(11 - i));54 }55 // Test the year wraps around.56 for (int i = 12; i <= 15; ++i) {57 year_month ym1 = ym - months{i};58 assert(static_cast<int>(ym1.year()) == 1233);59 assert(ym1.month() == month(11 - i + 12));60 }61 }62 63 { // year_month - year_month64 65 // Same year66 year y{2345};67 for (int i = 1; i <= 12; ++i)68 for (int j = 1; j <= 12; ++j) {69 months diff = year_month{y, month(i)} - year_month{y, month(j)};70 assert(diff.count() == i - j);71 }72 73 // TODO: different year74 }75 return true;76}77 78int main(int, char**) {79 // year_month - years80 ASSERT_NOEXCEPT(std::declval<year_month>() - std::declval<years>());81 ASSERT_SAME_TYPE(year_month, decltype(std::declval<year_month>() - std::declval<years>()));82 83 // year_month - months84 ASSERT_NOEXCEPT(std::declval<year_month>() - std::declval<months>());85 ASSERT_SAME_TYPE(year_month, decltype(std::declval<year_month>() - std::declval<months>()));86 87 // year_month - year_month88 ASSERT_NOEXCEPT(std::declval<year_month>() - std::declval<year_month>());89 ASSERT_SAME_TYPE(months, decltype(std::declval<year_month>() - std::declval<year_month>()));90 91 test();92 static_assert(test());93 94 return 0;95}96